Optical properties of magic clusters formed in In/Si(111) and Cr/Si(111) systems.

The optical properties of ultrasmall ordered indium and chromium quantum dots of identical size (magic clusters) in the In/Si(111) and Cr/Si(111) systems have been studied by differential reflection spectroscopy (DRS). Using the DRS data, the character of the magic clusters of each type has been elucidated. It is established that the magic clusters of chromium formed in the Cr/Si(111) system represent nanocrystals of chromium silicide (Cr/Si(111) is a reactive system featuring chemical interaction between the metal and the silicon substrate, which leads to silicide formation). The magic clusters of indium formed in the nonreactive In/Si(111) system represent a surface phase. [ABSTRACT FROM AUTHOR]